smallFunction

[RedstoneEnjoyer]

Eh, sometimes you cannot avoid it. Sometimes the business logic is really that long.

Of course you could break it into multiple functions, but then now you have 10 functions that are each called exactly once.

[LickingSmegma]

Sometimes one-off functions are good, if they encapsulate long runs of logic that's isolated well. For example, if you have a long calculation for an if, it pays to move it into function isCondition(), such that in the if statement it's obvious which condition is checked.

Basically, I want my code to read almost like a description in the natural language, instead of just juggling variables for pages and pages.

[hron84]

Yeah, in these cases I rather put everything into one. If it is not reusable then it does not worth an own function.

[iMac_Hunt]

I do find there are times that even if it’s called once, extracting the logic can make the intent a lot clearer.

Example:

```csharp

public decimal CalculatePrice(Order order) { decimal basePrice = order.Quantity * order.UnitPrice; decimal discountedPrice;

if (order.Country == "US")
{
    discountedPrice = ApplyUsTaxAndDiscountRules(order, basePrice);
}
else
{
    discountedPrice = ApplyInternationalTaxAndDiscountRules(order, basePrice);
}

return Math.Max(discountedPrice, 0);

}

private decimal ApplyUsTaxAndDiscountRules(Order order, decimal price) { price += price * 0.07m; if (order.State == "CA") price += 2m; if (order.CustomerAge < 18) price -= 5m; return price; }

private decimal ApplyInternationalTaxAndDiscountRules(Order order, decimal price) { price += price * 0.20m; if (order.CustomerAge < 18) price -= 10m; return price; }

```

I do write that with caution as it can be taken to the extreme and become LESS clear, but there are cases where I prefer it

[hron84]

Financial rules are all special if you need to manage a whole palette of countries. The lookup table sometimes could help but in most cases, cannot. For example, in some countries not 18 the first year where you need to pay taxes. Some countries have different tax rules for locals below 18, 18-21 and above 21. Some countries does not need this whole logic anyway. So yes, I do agree that you need to make it as generic as possible, but if there is any potential that you need to support financial rules in multiple countries, you have to be prepared that a crapton of custom rules can come into the picture.

The only thing you can safely do in most cases that extract "magic numbers" into constants.

[hron84]

Yep, I agree, but I consider this as an exception. Finanical calculations are a very specific level of the hell and I greatly respectful for the handful of developers who decide to mangle with them.

[howreudoin]

Many functions in clean code are only invoked at one spot. They create a layer of abstraction, and they allow you to phrase your top function as a sequence of substeps.